Cutter bit grinding jig



1948. H. SMILEY, JR 2,449,957

CUTTER BIT GRINDING JIG Filed Sept. 16, 1946 2 Sheegs-Shet 1 HUGH SMI'LEY, JR.

I N VEN TOR.

A'ITD RN EYS Sept. 21, 1948. H. SMILEY, JR 2,449,957

' CUTTER BIT GRINDING JIG I Filed Sept. l6, 1946 2 Sheets-Shget 2 HUGH WILEY ,JB.

IN VENTOR,

RNEYs Patented Sept. 21, 1948 UNITED q STATES PATENT OFFICE I 2,449,957 f CUTTER BIT GRINDING no Hugh Smiley, Jr; Henniker, .N. B.

I Application September 16, 1946, Serial No'. 697,312

The present invention relates genera-11y to immovements in work holders for edge tools while being'sharpened upon a rotary grindingwheel, and more specifically the invention involves an improved cutter-bit grinding jig or clamp appli-,

are made possible by the facile adjustment of the work holder. l v

The work holder is adapted for use with standard types of power operated grinding or abrading wheels, and the unitary appliance may be installed withfacility upon a bench or other support in operative relation to the grinding wheel.

A minimum number of parts are utilized, which may be manufactured'at low cost to production; and assembled with facility, to provide an appliance that is simple in construction and operation,.

and which may be manipulated with convenience to secure the desired adjustments. In combinatlon with the adjustable parts of the appliance a gauge is provided to determine and indicate the desired angle of the bit with relation to the wheel,-

and the resulting angle of the ground face of the bit.

trated one complete example of the physical embodiment of my invention wherein the .parts are combined and arranged in accord with one mode I have devised for the practical application of the principles of my invention; but it will-be-understood that various changes and alterations are contemplated .and may be made in these exemplifying drawings, within the scope of my appended claims without departing from the prins ciples of myinvention.

Figure 1 is a view in side elevation of a ,jig or appliance embodying my invention and holding an edge tool or bit against the peripheral or circumferential face of a rotary grinding wheeLfor abrading a side of the bit; and

Figure 2 is a top plan view of the appliance of Fig. 1.

Figure 3 is a transverse vertical sectionalview at lines-3 of Fig. 1 disclosing the protractor or gauge for setting the angularly adjustable work holder. u I

In the accompanying drawings I have illus 4 Claims. (Cl. 51-238) Figure 4 is a transverse vertical sectional view.

at line 4-4 of Fig. 2 through the adjustable head and arm of the appliance.

Figure 5 is a detail vertical transverse sectional view at line 5-5 of Fig. 2 through the work holding means. v

Figure 6 is a detail top plan view of a portion of the work holder with the edge tool in position for grinding its acute back face.

Figure 7 is a detail end view of the work holder adjusted to the grinding wheel for grinding an obtusely disposed back face of the edge tool or bit, and indicating the use of the protractor or setting gauge; and

Figure 815 a detail vertical longitudinal tional view at line 8-8 of Fig. 2 through the vertically adjustable arm as mounted on the supporting column or post.

In the preferred form of the invention shown in the assembly views Figs. 1 and 2, as well as in other views, a conventional rotary grinding or abrading wheel W is illustrated for grinding or sharpening an edge tool here shown as a cutterbit B, and I utilize a flat angular base I that is slotted to accommodate bolts or other means for rigidly fastening the appliance to the bench or other support for the wheel that rotatesor revolves ona horizontal axis.

An upright support in the nature of a solid cylindrical column or post 2 at its lower end is rigidly mounted in the base, and a horizontally disposed vertically adjustable lateral arm 3 is mounted on the post and clamped in adjusted position by means of a clamp bolt 4 mounted vin a split end of the arm, and secured by nut 5 on a protruding end of the bolt.

The horizontally arranged arm supports a split resilient clamping head 5 that is rotatable on a horizontal axis in a vertical plane, and for this purpose the head is provided with a rigid stud in whlch a preferably solid cylindrical supporting bar I0 is mounted for longitudinal adjustment, and a clamping bolt II is passed through holes in the split resilient side of the head and secured by nut l2 for clamping the head in fixed position on thebar in order that the head and bar may be rotatably adjusted to desired position.

-To retain the supporting bar against longitudinal movement within the head, a pair of laterally-adjustable collars l3 and M are mounted upon the banone at each side of the head, and

sec-.-

set screws or bolts l5 are utilized to fasten the collars in adjusted position.

As best seen in Fig. 3, one of the collars, as [3 is equipped with a radial needle or pointer l6 that co-acts with a fixed gauge plate [1 that is attached as by screws l8 upon a vertical face of the head 6, and the plate is provided with a scale calibrated in degrees ranging in right and left angles from zero up to twenty degrees, for use in accurately-setting they work holder, and bit B for sharpening its cutting edge.

One projecting end of the supporting bar I0. is provided with an adjustable weight I9, and a set screw or bolt 20, for counterbailancing the load of the work holder that is rigidly mounted upon the other end 2| of the bar, which is preferably oifset from, but parallel with the Plane;

the upper faces of these integral sections are provided with right angle grooves 24 and 25'.

For selective use with either of the two angu lar sections of the table, a slide plate 26 of rectangular shape, is fashioned on its underside with a tongue 21- complementary to the grooves 24 -25, and as indicated-in Figs. 2 land 6, the angular table 222 3- may be adjusted in position with one section transversely of the wheel and the other section disposed in a plane transversely of the axis of rotation of the wheel. The removable and adjustable slide plate 26 forming the holder for the bit, may be mounted for adjustment in a plane transversely of thegrinding wheel, as well as in a plane transversely of the axis of the wheel.

For retaining the edge tool or bit B in grinding position upon the plate 26, a pivotal guide block 28 is mounted on the upper face of the plate, and secured in adjusted position by means of a set screw or bolt 29', having a clamp shoulder 30, and threaded in a socket of the plate, and as best seen in Fig. 5, the set screw, by use of its shoulder, clamps the pivotal block in rotatably adjusted position.

To form a stop for the slide plate, and for precisely adjusting the plate and the pivotal guide block on the table, a set screw 31 is shown threaded in an upright bracket 32 of the table located at the grooved end of the table, and the screw is of ample length to engage the slide plate or carrier in various adjusted positions on the table.

In Fig. 2 the bit B is held by the guide block against the circumferential :abrading surface of the grinding wheel W, for grinding a sideface of the bit; in Fig. 6 the bit is set for abrading its bevel face at an acute angle; and in Fig. 7 the bit is set for sharpening the bit with an obtuse bevel face. The several settings for the bit are accurately and with facility determined and indicated by setting the pointer or needle IS with relation to the calibrated scale on the plate H, and adjrusting the various supporting parts of the work holder with relation to the wheel W.

The supporting arm 3 is adjustable vertically; the head 6 and bar [0 are pivotally adjustable in a vertical plane; the bar I0 is longitudinally adjustable and rotatably adjustable in its head with, relation to the wheel to present the work table v to the wheel; and the work table, together with the pivotally adjustable guide block may be presented to the wheel at Various selected angles.

By rotatably adjusting the bar l0 in the head 6, the work holder and its guide block mounted on the offset shank 2| of the bar may present a face of the bit to the grinding face of the wheel W on a. line with the transverse horizontal axis of the wheel, as well as within an ample nange above and below this line, for grinding operations. Due to the convexity of the grinding wheel, in, some instances, the dressed face of the bit is concave, and to remove this concavity the table and guide bar may be raised above or lowered below the median line of the wheel, to insure a flattened face.

By. means of the adjustable slide plate or holder 26 the pivotal guide bar may be pressed to hold:

the bit along the face of the grinding wheel, and the holder may be moved back and forth during the grinding operation to prevent local wear on the face of the wheel.

For grinding top, back and front angles or rakeson the bit the-work table may be adjusted with its section 23 parallel with the side of the wheel and the guide bar or block 28is set at the back or front rake desired. The top side of'the,

Having thus fully describedmy invention, what I claim as new and. desire to secure by Letters Patent is:

1. In a. work-support for use-with a grinding wheel; the combination with a stand having a vertically adjustable arm, and a head rotatably adjustable in the arm, of a longitudinally adjustable' bar rotatably mounted in the head and means for clamping the head and bar in adjustedposition, and a work-holder mounted on the bar in position for adjustment above and below the horizontal transverse axis of the wheel.

2. In a work support for use with a grinding wheel, the combination with a stand having a lateral arm, and a head rotatably adjustable-in the arm, of a longitudinally adjustable bar r0- tatably mounted in the head and having an axially offset shank, of a work holder rigidly mounted on the shank, and an adjustable guide block pivotally mounted on the work holder.

3. In a work support for use with a grinding wheel, the combination with a stand having a lateral arm, and a head rotatably adjustable in the arm, of a bar-having an axially offset shank and rotatably adjustable in the head, anjL- shaped table rigid with the shank, a removable holder adapted for selective use with the table, and an adjustable guide block pivotally mounted on the holder.

4. In a work support as described, the combination with a support, a head rotatable in the sup- 5 .0 an axially ofi'set shank, a table rigid with the shank, a work holder adapted for co-action with the table, and a guide block mounted for pivotal adjustment on the work holder.

The following references are of record in the 10 file of this patent:

6 UNITED STATES PATENTS Number Number Name Date Carpenter Apr. 2, 1912 Downer Mar. 19, 1918 Sumbling Feb. 24, 1920 Smith Jan. 2, 1923 FOREIGN PATENTS Country Date Australia July 2, 1943 

